Claims
- 1. A forging compound for at least partially coating workpieces of titanium and its alloys prior to hot die forging of the workpiece, said forging compound comprising a mixture of boundary layer particles and a powder of vitreous components, said boundary layer particles remaining solid at forging temperatures and being selected from boron nitride, graphite and mixtures thereof, said boundary layer particles being less than 40% and more than 7% by weight of the total vitreous and boundary layer components of the forging compound, said powder of vitreous components being substantially free of materials which have a tendency to corrosively attack the forging dies and comprising diboron trioxide in an amount between about 60 to 75% by weight of the vitreous components and silica glass to provide a desired viscosity during forging, the balance of the vitreous components comprising a metal oxide wetting agent to promote spreading of the vitreous components over the surface of the workpiece during forging, the metal oxide wetting agent being between about one-half of 1 to 5% by weight of the vitreous components and being an oxide of cobalt.
- 2. The compound of claim 1 wherein the boundary layer particles are boron nitride particles and the metal oxide is cobalt oxide.
- 3. The compound of claim 1 wherein the boundary layer particles are of a size that at least 95% thereof pass through a 325 mesh screen and comprise between about 7 to 25% by weight of the total of boundary layer particles and vitreous components, the diboron trioxide comprises between about 67 to 75% by weight of the vitreous components, and the metal oxide comprises between about 1 to 3% by weight of the vitreous components.
- 4. The compound of claim 3 wherein the boundary layer particles are boron nitride and the metal oxide is cobalt oxide.
- 5. The compound of claim 4 having the following composition:
- ______________________________________% By Weight Component______________________________________25 Boron nitride75 Vitreous components______________________________________
- with the vitreous components comprising
- ______________________________________% By Weightof Vitreous Components Component______________________________________67 Diboron trioxide31 Silica glass frit 2 Cobalt oxide______________________________________
- 6. The compound of claim 4 having the following composition:
- ______________________________________% By Weight Component______________________________________14 Boron nitride86 Vitreous components______________________________________
- with the vitreous components comprising
- ______________________________________% By Weightof Vitreous Components Component67 Diboron trioxide31 Silica glass frit 2 Cobalt oxide______________________________________
- 7. The compound of claim 1 wherein the diboron trioxide, silica glass frit, and metal oxide have been reacted in advance of use to form a borosilicate glass containing the metal oxide.
- 8. A forging compound as set forth in claim 1 wherein said boundary layer particles are of a size less than that at which at least 95% of the particles pass through a 40 mesh screen.
- 9. A forging compound as set forth in claim 1 wherein said vitreous components are substantially free of oxides of lithium, sodium, potassium, vanadium and phosphorus all of which tend to corrode forging dies.
- 10. A forging compound as set forth in claim 1 wherein said vitreous components are substantially free of oxides of calcium, magnesium, lead and cerium to retard crystallization of the forging compound during preheating.
BACKGROUND OF THE INVENTION
The invention herein described was made in the course of or under a contract, or subcontract thereunder, with the U.S. Air Force.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1,285,084 |
Jul 1965 |
DT |
2,430,249 |
Jun 1974 |
DT |